The dubious winner of today's "are you bleeping kidding me with this app?" award goes to The Clorox Company, which should have provided me with some eye bleach for their winning entry Sock-It: Leave the sock in the hamper (free, as if anyone would pay for this).
From the App Store description:
Forget the sock on the doorknob – whenever the need for privacy arises, grab your phone, open Sock-It and tap it. Once activated, the Sock-It app uses iBeacon technology to let anyone who comes near your door know that you're, well... a little busy at the moment. It's simple, just turn on the "Do Not Disturb" function and anyone who comes close and also has downloaded the app automatically will receive a notification letting them know it's probably best to give you some space for a while. After all, who really wants a sock on the door?
Your roommate/friend/mom/whomever also needs to have the app on his/her iPhone to get notification that you are otherwise, erm, engaged in activities that you'd rather not have interrupted (like sleeping, for example).
All college roomies and teen-aged boys need to download Sock-It now. That is all.